I had gotten one of these before and it turned out to be too big and bulky to be able to use for very long. Plus it had to be plugged in to use it and that restricted a lot of movement. When your muscles are sore and you are trying to loosen them up, you don't want to also have to fight with a cord or deal with a heavy massager.
These problems are solved with this massager. Since it is battery operated, there is no cord to worry about. You just have to make sure that it is charged. It is also smaller and weighs less so it is easier to hold and use for a longer period of time. Much better than the corded version and has the same power.